Missing Origin Validation in WebSockets in RabbitMQ Server - CVE-2026-67405
Published: July 9, 2026 / Updated: September 28, 2026
Vulnerability identifier: #VU137240
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-67405
CWE-ID: CWE-1385
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to compromise the integrity of cross-origin WebSocket interactions.
The vulnerability exists due to missing origin validation in the Web-MQTT and Web-STOMP WebSocket handlers when processing WebSocket upgrade requests. A remote attacker can run malicious JavaScript in the victim's browser to compromise the integrity of cross-origin WebSocket interactions.
Exploitation requires user interaction and is only possible when the non-default configuration use_http_auth=true for Web-STOMP or ssl_cert_login=true for the affected plugins is enabled.
Affected software
RabbitMQ Server
How to mitigate CVE-2026-67405
Install security update from vendor's website.
RabbitMQ Server - addressed in versions 3.13.15, 4.0.20, 4.1.11, 4.2.6